Implement C API function PyUnicode_Tailmatch.

Author: fangerer

graalpython/com.oracle.graal.python.cext/src/unicodeobject.c

@@ -491,3 +491,8 @@ PyObject * PyUnicode_Decode(const char *s, Py_ssize_t size, const char *encoding
 PyObject * PyUnicode_DecodeASCII(const char *s, Py_ssize_t size, const char *errors) {
 	return PyUnicode_Decode(s, size, "ascii", errors);
 }
+
+UPCALL_ID(PyUnicode_Tailmatch);
+Py_ssize_t PyUnicode_Tailmatch(PyObject *str, PyObject *substr, Py_ssize_t start, Py_ssize_t end, int direction) {
+	return UPCALL_CEXT_L(_jls_PyUnicode_Tailmatch, native_to_java(str), native_to_java(substr), start, end, direction);
+}

graalpython/lib-graalpython/python_cext.py

@@ -770,6 +770,13 @@ def PyUnicode_AsUnicodeEscapeString(string):
     return _codecs_module.unicode_escape_encode(string)[0]
 
 
+@may_raise(-1)
+def PyUnicode_Tailmatch(s, substr, start, end, direction):
+    if direction > 0:
+        return 1 if s[start:end].endswith(substr) else 0
+    return 1 if s[start:end].startswith(substr) else 0
+
+
 ##################### CAPSULE